Furnace-door



nois, have invented certain new and useful opposite end is prolonged soas to project betion of the device, so that the slide covering .gated openings to, for the admission of air into of the drawings, which is not the case in the UNITED STATES PATENT 0 Finch.

HARRIS HIGGINS, OF CHICAGO, ILLINOIS.

FURNACE-DOOR.

SPECIFICATION forming part of Letters Patent No. 268,889, dated December 12, 1882.

Application filed October 13, 1882. (N0 model.)

To all whom it may concern:

Be it known that I, HARRIS HIGGINS, of Chicago, county of Cook, and State of Illi- Improvements in Furnace-Doors,-of which the following is a full, clear, and exact description, that willenable others to make and use the same, reference being had to the accompanyingdrawin gs, and to letters ot'reference marked thereon, forming a part of this specification.

This invention relates to an improvement on Letters Patent No. 238,006, the object being to make additions and changes in the'con'structhe draft-openings in the furnace-door is automatically adjusted to admit air into the combustion-chain her, as will be hereinafter more fully set forth in detail.

Figure 1 is a front elevation of a boilerfront embodying my improvement; Fig. 2, a vertical transverse section of afurnacr-door in the plane :rzr, Fig. 1; and Fig. 3, aview in perspective of my improved feature.

Reterrin g to the drawings, A represents the furnace-door proper, the general features of which are of the same form and construction as that set forth in the patent above referred to. A generaldescription of the door will therefore be omitted, the description in this case being confined to my improvement and the parts relating thereto.

The furnace-door is provided with the elonthe furnace.

B represents a slide set in the face ofthe door, and is adapted to have a vertical movement. This slide is composed of a series of horizontal bars,b, connected by end pieces running at rightangles, which correspond in numher to the draft-openings.

The back or stationary end of the lever O is pivoted to the back end of the door, while the yond the end of the door, as shown in Fig. 1

patent referred to above. The slide B and lever 0 are connected near their longitudinal center by the link D. .The lever G is connected at a point near the loose end with the piston-rod a of the dash-pot E.

drawings, and may be thrown upward in a ver-' tical plane out of the way, but cannot drop downbelowthe position shown in Fig. 3, by

reason of the stop a In the patent referred to above the slide covering the draft-openings in the face of the door had to be raised by hand each time that fresh fuel was added to the fire, as that is the time that the draft-apertures in the face of the door are required to be wide open, and then gradually closed, as the varying wants ot'the fire may require, by means of the piston descending in the dash-pot, which is tilled with oil or other suitable liquid body.

The heel or back end of the arm H is provided with the oft'seth, whichpermits the outer end of the lever G to drop down as the piston in the dash-pot descends. Now, when the furnace-door is opened the projecting end of the leverO passes underneath the arm H, and

when the door is closed the end of the leverG V rises on the upper side of the arm H and automatically raises the slide and uncovers the draftopenings in the face of the door.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is-

In a furnace-door, thacombinatiou, with the slide B and the dash-pot E, of the lever 0, having a suitable connection therewith, and the adjustable arm H, whereby the act of closing thedoor has the effect of automatically raising said slide and uncovering the draftopenin gs provided for the admission of air into the combustion-chamber, substantially as described.

HARRIS HIGGINS.

Witnesses L.-M. FREEMAN, L. B. OoUPLAND. 

